Salivary duct carcinoma of the palate

Salivary duct carcinoma (SDC) is a rare and highly aggressive malignancy of the salivary glands. It occurs almost exclusively in the major salivary glands, particularly the parotid, while in much less frequency in the minor salivary glands and the case showing exophytic growth in the oral cavity like the present case is extremely rare. This report is of an 82-year old man with SDC of the palate. A pedunculated discoid mass of 15 mm in diameter was on the right-sided paramedian posterior end of the hard palate. The lesion was excised and the histopathological examination showed the mass composed of various-sized carcinoma cell nests presenting solid to cribriform growth pattern with scanty interlacing stroma and comedonecrosis, and vascular and lymphatic invasion. The diagnosis was SDC. The immunohistochemistry of the tumor cells was positive for proliferating cell nuclear antigen and Her2/neu. The Ki-67 labeling index was approximately 80%. There has been no evidence of local recurrence or metastasis 24 months after surgery. We added a case of SDC arising from the minor salivary gland, which may be representing the early phase of highly aggressive SDC.